Obstruction, biliary

The bile acid sequestrants are contraindicated in patients with known hypersensitivity to the drugs. Bile acid sequestrants are also contraindicated in those with complete biliary obstruction. These drags are used cautiously in patients with a history of liver or kidney disease Bile acid sequestrants are used cautiously during pregnancy (Pregnancy Category C) and lactation (decreased absorption of vitamins may affect the infant). 

A9. Aronsen, K. F., Liver function studies during and after complete extraheptic biliary obstruction in the dog. Acta Chit. Scand. Suppl. No. 275, 54 and 76 (1961). 

Q13 is used in pruritus associated with partial biliary obstruction... 

Questran contains colestyramine, a lipid-regulating drug that acts as a bile acid sequestrant it is also used in pruritus associated with partial biliary obstruction and primary biliary cirrhosis. 

The presence of LP-X in the plasma of patients with liver disease has been considered as a sensitive indicator of biliary obstruction and, thus, useful in the differential diagnosis of diseases of the liver (S29, Wl). However, the recent demonstration (see Section 8.2) that particles resembling LP-X occur also in the plasma of patients with LCAT deficiency poses serious reservations regarding the specificity of the proposed test. 

Switzer, S., Plasma lipoproteins in liver disease I. Immunologically distinct low-density lipoproteins in patients with biliary obstruction. J. Clin. Invest. 46, 1855-1866 (1967). 

Speciai risk patients Patients on dialysis may develop orthostatic hypotension monitor blood pressure closely. Initiate treatment under close medical supervision for patients with biliary obstructive disorders or hepatic insufficiency. Correct the condition of patients with depletion of intravascular volume before initiating therapy and monitor closely. 

Telmisartan- As the majority of telmisartan is eliminated by biliary excretion, patients with biliary obstructive disorders or hepatic insufficiency can be expected to have reduced clearance. Use telmisartan with caution in these patients. 

Hypersensitivity to bile acid sequestering resins or any components of the products complete biliary obstruction (cholestyramine only) bowel obstruction (colesevelam only). 

Biliary tract Administer with caution to patients with known or suspected cholelithiasis or biliary tract disease. Contractions of the gallbladder or biliary smooth muscle could precipitate complications including cholecystitis, cholangitis, and biliary obstruction. 

Hepatic disease or biliary obstruction - In general, total daily dosage greater than 4 g should not be necessary. 

Renal function impairment Cephalosporins may be nephrotoxic use with caution in the presence of markedly impaired renal function (Ccr less than 50 mL/min/1.73 m ). Hepatic function impairment Cefoperazone is extensively excreted in bile. Serum half-life increases 2-fold to 4-fold in patients with hepatic disease or biliary obstruction. 

The following drugs also are indicated in Ascariasis. Piperazine citrate (if intestinal or biliary obstruction) thiabendazole. 

If a patient with liver disease also has ascites and oedema, the Vd of some drugs may be increased and biliary obstruction may impair the excretion of drugs cleared through the bile. 

Castor oil is a bland oil that is hydrolyzed in the gut to yield ricinoleic acid, the active purging agent. This hydrolysis requires bile, a fact that is sometimes overlooked when castor oil is given as a laxative before radiography in biliary obstruction. The ricinoleic acid acts on the ileum and colon to induce an increased fluid secretion and colonic contraction. 

Urinary excretion is the major elimination path for most cephalosporins. When prescribing cephalosporins to patients with renal failure, practitioners must consider dose reduction or dose interval extension (Table 45.2). Renal tubular secretion contributes to the elimination of some cephalosporins, and an increase in cephalosporin plasma concentrations may occur when probenecid blocks renal tubular secretion of cephalosporins. Biliary elimination is important for some cephalosporins. Cefmetazole, cefoperazone (Cefobid), cefoxitin, and ceftriaxone achieve biliary concentrations greater than those in plasma. After parenteral administration of cefoperazone, 70% of the dose appears in the bile within 24 hours. Practitioners should decrease the dose of cefoperazone when prescribing for patients with hepatic failure or biliary obstruction. Metabolism is not a major elimination path for most cephalosporins. Cefotaxime is one of the few cephalosporins having an active metabolite, desacetyl cefotaxime. 

Piperazine is an appropriate alternative to mebendazole for the treatment of ascariasis, especially in the presence of intestinal or biliary obstruction. Cure rates of more than 80% are obtained following a 2-day regimen. 

Dosage in renal and/or hepatic impairment Do not exceed 4 g/day in those with liver disease and/or biliary obstruction. Modification of dose usually not necessary in those with renal impairment. Dose should not exceed 1-2 g/day in those with both hepatic and substantial renal impairment. 

Contraindications Complete biliary obstruction, hypersensitivity to cholestyramine ortartrazine (frequently seen in aspirin hypersensitivity)... 

Factors which decrease availability of the vitamin include (1) biliary obstruction (2) liver damage—cirrhosis, toxins (3) poor food preparation (vitamin is strong-add, alkali, light, and reduction labile) (4) impaired lipid absorption in gut (5) presence of antagonists (6) ingestion of mineral oil (7) sterilization of gut with antibiotics and sulfa drugs and (8) excessive excretion in feces. Availability may be increased by way of storage in the liver and absorption aids, such as bile salts. 

R2. Rundle, F. F., Perry, D., Cass, M., and Oddie, T. H., Rise in serum bilirubin with biliary obstruction and its decline curve after operative relief. Surgery 43, 555-562 (1958). 

A word of comment on the high Cu64 content of the bile seems justifiable, since the exact chemical form of copper excreted in the bile has not been determined. The possibility that ceruloplasmin or some copper-containing metabolite of ceruloplasmin is normally excreted in the bile has not been carefully examined. The abnormal elevation of the serum ceruloplasmin level in acute biliary obstruction (7), and the abnormally low serum ceruloplasmin seen in some cases of advanced liver disease, particularly Wilson s disease (2, 3), are in keeping with the liver being the site of ceruloplasmin synthesis and excretion. 

Therapeutic uses The bile acid binding resins are the drugs of choice (often in combination with diet or niacin) in treating Type lla and lib hyperlipidemias. [Note In those rare individuals who are homozygous for Type lla, that is, for whom functional LDL receptors are totally lacking, these drugs have little effect on plasma LDL levels.] Cholestyramine can also relieve pruritus caused by accumulation of bile acids in patients with biliary obstruction. 

Pharmacokinetics Intravenous injection of vincristine or vinblastine leads to rapid cytotoxic effects and cell destruction. This in turn can cause hyperuricemia due to the oxidation of purines to uric acid. The hyperuricemia is ameliorated by administration of the xanthine oxidase inhibitor, allopurinol (see p. 417). The agents are concentrated and metabolized in the liver and are excreted into bile and feces. Doses must be modified in patients with impaired hepatic function or biliary obstruction. 

For oral administration, the water-soluble preparation menadiol sodium phosphate, is used in patients with hepatic disease, especially biliary obstruction. The usual dose is 10 mg daily. Alternatively, phytomenadione tablets may be used in those patients who do not have impaired fat absorption. 

The recommended dietary allowance (RDA) for vitamin D is 5 fig (200 IU)/d, but this value includes casual exposure to sunlight without regard to lifestyle or climate. For individuals who do not receive adequate sunlight because of illness, advanced age, or are otherwise shut in, the actual daily requirement for vitamin D3 could be as much as 15 fig/d. Vitamin D3 deficiency also may occur with chronic biliary obstruction and steatorrhoea limiting intestinal absorption of vitamin D3 and lead to osteomalacia [44], Another factor is the increased use of sunscreens among Western societies, that limits the penetration of UV photons to the site of vitamin D3 synthesis [41,45,46],... 

Insufficient digestive agents Biliary obstruction Chronic liver failure Chronic pancreatitis Cystic fibrosis Lactase deficiency Pancreatic cancer Pancreatic resection Sucrase-isomaltase deficiency... 

Bilirubin Produced from haemoglobin during degradation of erythrocytes. Found in bile 5-21 pmol/L Raised in hepatocyte dysfunction, biliary obstruction and haemolysis... 

Pale stools are a sign of biliary obstruction. Normally, bile is secreted into the intestine, where the majority is converted to the faecal pigment stercobilin. If there is a biliary obstruction bile secretion is reduced and this conversion cannot take place, and so the stools do not have the usual coloration. Where there is complete obstruction, such as in biliary atresia, the stools may be white. 

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